On a tuesday that happens to be Earth Day, the world falls away as the Cessna lifts into a fat blue sky. Megan Kimble of Edible Baja Arizona and Seth Cothrun of the Sonoran Institute sit in back, offering me the copilot seat. We’re flying today with LightHawk, a nonprofit environmental organization that uses volunteer pilots and their aircraft for conservation—today, our goal is to trace the length of the Santa Cruz River. Our pilot, Will Worthington, is a former chief civil engineer for the Central Arizona Project. He knows water. And he knows history. Today, he’s our guide at the controls as we fly the river of the Holy Cross, 200 miles from its headwaters in the San Rafael Valley to the Gila River, in two hours. The last time I made this trip, it took eight years.
This will be a celebration. When I traveled the Santa Cruz for my book Dry River, I did it by car, by foot, and by horseback. This will be a perspective without the inconsistency of roads, without climbing barbed wire fences and steel-walled borders, without navigating the political boundaries of three separate nations the river runs through. It will be from the perspective of continuity, of the connection we all have with water in a desert land.
From Canelo Pass, the San Rafael Valley drops away to the south. Ropes of green, where oak and juniper mark every wrinkled drainage, crisscross a broad rolling plain. Mountains shoulder the valley—the Huachucas on the east, Patagonias on the west—their peaks blue-gray above a brown world. Seventy-five miles from Tucson, we fly over the headwaters of the Santa Cruz River. Like the veins of a giant cottonwood leaf, these tributaries gather a river that spills into Mexico.
Between one and two million years ago, shallow runoff poured into these intermountain basins, charging aquifers and depositing gravel and sand from the eroded aprons of the mountains. This was the time of the great inland seas, like Lake Cochise. In this valley, as sediments moved among previously isolated basins, a “proto” Santa Cruz River formed, flowing only south. Over time, the river continued to join basin after basin, raising terraces in one place, only to redistribute them elsewhere. Eventually, the river took its present shape, surging across this land, connecting basins like threading beads on a string until finally the beads slipped the necklace to join a young Gila River on its way to the Colorado River and the Sea of Cortez. Ebb and flow, the recurrent pattern of life, gave birth to the Santa Cruz River.
“Looks like a scene from the Pleistocene,” I say into my headset over the roar of the engine.
“They’ve found mammoth kill sites on the San Pedro River in the next valley,” Seth adds.
I imagine the first people who trickled into the San Rafael Valley between 10,000 and 12,000 years ago, Paleo-Indians following the trails of mammoth and bison. As the Ice Age drew to a close and the land relaxed under warmer skies, this valley may have helped nomadic people settle into communities and become hunter-gatherers.
At the Lone Mountain Ranch, 10 miles east of us in the Huachuca Mountains, archaeologists have uncovered human occupations spanning more than 11,000 years. Today, a gerrymander of oak woodlands and grasslands drapes hills cut by riparian drainages, ephemeral streams reduced in the dry season to chains of pools. Lone Mountain is littered with prehistory: boulders etched with human figures; fire-cracked rocks circling roasting pits; grinding stones resting among flakes of obsidian, pottery shards, and small, triangular projectile points.
The San Rafael Valley holds a long, nearly continuous presence of humans. Ten thousand years ago, people of the Cochise culture shared the grasslands with fantastic animals like lions and camels, and long-fanged dire wolves. They camped here to harvest wild grains and parch them in hearths of incandescent coals. Three thousand years ago, the area was home to people who roasted agaves and feasted on the dark, sweet, molasses-like cores.
For thousands of years, this place has drawn people, the latest being 19th century homesteads and cattle ranches. What they all have in common is their connection to the valley, to the resources it provides, and to the river that sustains them. The entire Santa Cruz River, from the headwaters in this valley to the Tucson basin and beyond, braids together the footpaths of humans dating from prehistory forward. The river has made it possible for people to find their way in the world.
“There’s the border,” says Will. “Comes up quickly—we’re in Mexico. Can you see water in the river?”
“Yes,” Seth says. “There’s water. And fields—what are they growing? Alfalfa?”
At the bottom of the San Rafael Valley, we trace an undivided ribbon of trees. Cottonwoods rise out of the riverbanks like dark smudges among polygons of bright green. A river in the service of agriculture. Orchards and alfalfa fields signal the region’s principal economies: cattle ranching and apples.
“And here’s the town of Santa Cruz,” I say, pointing ahead. “The town that gave the river its name.”
The bell tower of a church with its eggshell dome and simple cross rises out of a crowd of metal rooftops. This is where Father Eusebio Francisco Kino founded a Jesuit mission in 1693. Kino named it “Santa María de Suamca,” combining in his usual way both the Spanish and native tongues (suamca is an O’odham word meaning “immaculate”). The river and the town were named for a wandering Spanish fort, Santa Cruz de Terrenate, which began on the San Pedro River but moved and remained here until the end of Spanish rule. Eventually, Santa María de Suamca became the town of Santa Cruz, and the Rio de Santa María became known only as the Santa Cruz River.
Soon, we fly above the town named for a man raised from the grave, San Lázaro. Here, the Santa Cruz River renews itself, beginning its trademark U-turn to loop around the south-pointing finger of the Sierra San Antonio before flowing northwest back toward Arizona.
San Lázaro, like the village of Santa Cruz, is a ranching and agricultural community, whose 900 residents depend on the perennial flow of the river. One way that the river’s importance to the community has manifested itself is in a conservation program called Los Halcones, the Falcons.
A decade ago, Los Halcones rose out of the inspiration of Joaquin Murrieta, who was then the culture and conservation director of the Sonoran Institute’s Sonoran Desert Ecoregion Program. The Tucson-based Sonoran Institute works to help communities make decisions and policies that respect both the land and its people. Joaquin, who grew up in northern Sonora and received his Ph.D. at the University of Arizona, believes that the way to help preserve the Santa Cruz is to engage people on both sides of the border. In San Lázaro, Joaquin began meeting with local ranchers and farmers, but soon realized that better progress could be made by involving the town’s youth. Los Halcones was born when the Sonoran Institute rehabilitated an old clinic building, giving the teenagers a place to meet and organize cleanup campaigns and fieldtrips for restoration work and surveying bird life.
One of the goals of Los Halcones is to work with ranchers around San Lázaro to find alternative sources of water for cattle, excluding them from the riparian area where they trample banks and graze on young cottonwoods and willows that would otherwise provide food and shelter for wildlife.
Today, Los Halcones continues with the help of the regional, cross-border conservation organization, Sky Island Alliance, also based in Tucson. “Last year,” says SIA’s Christopher Morris, “we installed just over five kilometers of fencing [to keep cattle out of the river] with the goal of being able to revegetate the riparian gallery. We also installed about 575 willow pole plantings with help from the residents.”
“The environment doesn’t have borders,” says Sergio Avila, SIA’s program manager. “People from both the U.S. and Mexico share a closeness to it.”
As we turn toward Arizona again, I look toward the Sierra de Pinitos whose upwelling flanks bend the river from south to north, and the distant Sierra Azul, land of ocelots and jaguars. The people of San Lázaro, following after the town’s namesake, are resurrecting a river.
“I’ve heard that the river never flowed its entire length,” says Will.
“Only in flood,” I say. “Historically, the Santa Cruz only came to the surface in about five or six reaches, or stretches of the river, one of them right here near Kino Springs. These are the places where people lived, where Padre Kino established his missions and visitas: Guevavi, Calabasas, Tumacácori, and San Xavier. The water was life.”
I search the mesquite-smudged banks of the dry riverbed near Rio Rico for the mud walls of Guevavi, Kino’s first mission in what is now Arizona. Megan taps my shoulder and points to a sudden bloom of green in the channel. “Outflow from the Nogales International Wastewater Treatment Plant,” I say. “The cottonwoods start here and the gallery stretches north all the way beyond Tubac. A river reborn from flushing toilets.”
Seth reminds us of the cottonwood die-off from 2005, how scientists learned that inadequately treated effluent from the facility was growing algae that choked off the trees’ water and nutrients. “Caught us completely unawares,” he says. “So the Sonoran Institute began tracking the health of the river and publishing a ‘Living River Report.’”
The facility, which has served both sides of the border since the 1940s was due for an upgrade, especially since between 1990 and 2000 the population on the Mexican side grew to more than 200,000 people. A $60 million expansion came online in 2009, and the difference in water quality was astounding. In just three years, the Institute’s sample survey from Rio Rico to Tubac showed the population of native longfin dace and nonnative mosquitofish increase from two to nearly 2,000.
North of Tubac, the river channel begins to change, broadening and deepening into high-walled chocolate banks. “See where the cottonwoods disappear? We’re over the Tohono O’odham Reservation. I say. The river retreats underground where it flows into these deep intermountain regions with thousands of feet of valley fill. It always has. In 1852, despite a wet summer monsoon season, U.S. Boundary Commissioner John Russell Bartlett noted that about nine miles north of Tubac, the Santa Cruz River went dry.
Seth mentions the former mesquite bosque that once blanketed the desert south of Martinez Hill where the Santa Cruz once resurfaced. “It’s all gone,” he says, “with the river.”
“The O’odham have created a restoration site at Martinez Hill,” I say. “Using Colorado River water, the tribe has a forest of cottonwoods and willows on the dry banks of the Santa Cruz. Temperature drops 15 degrees when you walk into it.”
I point out the gleaming San Xavier del Bac Mission off to the left. “The river originally flowed closer to the mission. Sam Hughes, one of Tucson’s pioneers, caused the big ditch we now call the Santa Cruz River after his irrigation works went awry in the 1890s. All this was farmland before then.”
“By the 1980s,” Will adds, “the farms in the San Xavier district were largely fallow, primarily due to lack of water.” Will explains that the O’odham sued Tucson and others for taking water for which they had prior rights. The case resulted in the Water Rights Settlement Act, which stipulated the tribe would get 27,000 acre-feet of CAP water within 10 years. “The Bureau of Reclamation completed the aqueduct and had water delivery as promised, though the O’odham were not ready to take delivery immediately. Looks like the San Xavier farms are doing well.”
I chew on the irony and it’s like biting on aluminum foil. We have our own river, yet we must import another one—the Colorado—from 300 miles away and lift it 2,400 feet through pumping plants, inverted siphons, canals, and pipelines for the spigots of Phoenix and Tucson. Nature undone. Gravity overcome by coal.
As Seth points out, the Santa Cruz has sustained people for 13,000 years, sustained agriculture for over 4,000 years. It is why Tucson is here after all. “We must reconnect with the river,” he says. “It’s not simply a flash flood basin running through our town that is empty 10 months a year. If we want to build a movement that focuses on growing appropriate crops, that supports local farmers and ranchers, and restaurants that support those farmers and ranchers, then we can’t ignore the river that runs right through our heart.”
The peak called A Mountain comes into view and beneath it, the dry swath of river that is the birthplace of Tucson. Adobe walls, made from the dirt beneath them, enclose an orchard: Mission Gardens. The four-acre plot is where friars once tended fruit trees and vegetables. I recall a recent visit to the 200-year-old Franciscan church at Tumacácori, where work has begun to re-establish historical fruit trees at the mission’s original orchards and gardens. As part of the Kino Heritage Fruit Trees Project, researchers combed Father Kino’s journals and other early accounts. They searched mission communities, ranches, and abandoned farms in Sonora as well as ghost towns and the backyards of 19th century homes in southern Arizona. After locating colonial period trees, they collected seeds and cuttings and grew them at nurseries like Tucson’s Desert Survivors.
Park Ranger Vicki Wolfe had given me a tour of the Tumacácori orchard. “We are planting fruit trees from stocks introduced in the region by Jesuit missionaries in the 17th and early 18th centuries,” she explained. “Apple, pomegranate, fig, quince, pear, and others, as identified by the project.” The trees were small, but I pictured in a few years walking along shaded paths beneath spreading branches of ripening fruit. I imagined tasting the sweet flavor of Spanish history.
As part of the Tucson Origins Heritage Park, the newly reconstructed Mission Gardens under A Mountain has become another home of the Kino fruit trees. But the gardens will do more than represent some monk’s quiet retreat. This is becoming a one-of-a-kind living museum. From the Hohokam and Tohono O’odham to the Spanish, Mexican, Chinese, and territorial Anglo-Americans, Tucson’s first farmers will be honored by interpretation of the longest known history of cultivation in the United States.
Will asks permission from the tower at Tucson International Airport to fly into their airspace. “We’re on a reconnaissance mission of the Santa Cruz River,” he says.
“We’ll try to keep traffic away from you,” says a voice on the radio.
Picacho Peak lifts its dark head in the distance. Near Avra Valley Road, we fly over a straight line of green. “That’s the CAP aqueduct,” Will says. “It goes underground as a siphon to get beneath the railroad, I-10, and the Santa Cruz River before reappearing as an open canal again.”
Tucson, Will explains, had been the largest city in North America entirely dependent on groundwater. “With alarming rates of groundwater overdraft, Tucson was destined for traumatic changes in lifestyle. The CAP was basically their salvation.”
I think about how a thousand years ago, the Hohokam built their canals in this same place to irrigate their fields of corn and squash. I imagine circular pit houses of brush and mud among the irregular geometry of green, crowding a river of cottonwoods. The Santa Cruz River, more the dry aftermath of water than a flowing desert river, connects more than a landscape. It connects the past with the present.
We can’t go back, even a hundred years, in terms of the way we use the river. But we can get better. I grew up with Beat the Peak, Tucson Water’s public education effort to address summer shortfalls before the arrival of the Colorado River. The program has led to an awareness of the importance of saving water all year. Today, Tucson Water focuses on being water-smart with programs like Conserve to Enhance (C2E), which links individual water conservation directly to restoration of urban washes and riparian areas. By tracking how much water they save at home, participants can donate their savings to environmental restoration projects. In southern Arizona, participants have already banked more than 3.2 million gallons of water for the environment.
The Sonoran Institute’s vision for the Santa Cruz River includes enhancing water infiltration, securing river flows, and protecting and raising groundwater levels. The Institute’s annual Living River Report and water quality monitoring at Rio Rico are just two examples of their ongoing work. “What’s exciting to us,” says Emily Brott, SI’s project manager, “is that it’s about engaging the community.”
She sees a future where communities work for land and water policies that support the conservation of our natural and cultural resources, where people look for a return of the river.
From a distance, all things look small. Like the planet looks small from the distance of the moon. Small, as in NASA’s image of Earth, known as “the blue marble,” from Apollo 17 that has adorned Earth Day flags since the 1970s. From this perspective, you see how connected we all are, and how this place that connects us is all we have in the black emptiness of space. It doesn’t take much imagination to unwind our long history here in this very valley—hunter, forager, farmer, consumer—and see how we all have relied on one pale blue thread in a vast desert place. The Santa Cruz River, our home. ✜
Sonoran Institute. 44 E. Broadway Blvd., Suite 350. 520.290.0828. SonoranInstitute.org.
Visit LightHawk.org to learn about how volunteer pilots donate flights to elevate conservation.
Ken Lamberton’s latest book is Dry River: Stories of Life, Death, and Redemption on the Santa Cruz (University of Arizona Press, 2011). His next book, Chasing Arizona: One Man’s Yearlong Obsession with the Grand Canyon State, is forthcoming from UA Press.