In 1913, the Santa Cruz River stopped running past Tucson. No dam blocked it. The water table beneath its bed had simply dropped below the sand, and the river went underground and stayed there. Today, more than half a million people live on that dead river in a desert that receives about a foot of rain in a good year, and for decades they drank water that had been underground for thousands of years, pulling it out faster than the sky could put it back.
Arizona had no law against that. Arizona had no law about groundwater at all. The strange thing is how it started. It did not start with a drought.
It started with a ditch. In 1888, a Tucson businessman named Sam Hughes had a trench dug near what is now St. Mary’s Road, cutting into the gravel of the Santa Cruz to catch the water moving underneath it. Farmers had tapped that underflow for a very long time.
Hughes only wanted to intercept a little more of it, a little earlier, and sell it. Then in October 1889, a small flood came down the valley and found the ditch. Water that had spread across a wide, shallow floodplain for centuries was suddenly funneled into a narrow cut. Where it fell out of the end of that cut, it began to dig.
Geologists call the result a head cut, and it eats backward upstream against the current. By the following summer, the Santa Cruz had swallowed about three miles of its own bed. Within a year, the raw gash had traveled south almost to Mission San Xavier del Bac, nine miles away. The floods of 1890 made it worse.
Today, the Santa Cruz between downtown Tucson and San Xavier runs in a trench as much as thirty feet below the land beside it, and the researchers who studied it place a large share of the blame on Sam Hughes’s ditch. A river that has cut itself thirty feet down cannot flood its own fields anymore. It also cannot hold up a water table. The groundwater drains toward the low point, and the low point had just moved thirty feet.
Before that, this had been one of the best-watered places in the Southwest. In 1886, the Arizona Mining Index counted eight irrigation ditches running through the Santa Cruz Valley opposite Tucson. There were roughly nine miles of river that ran year-round. Cottonwood forests stood along the banks from San Xavier north to the Cañada del Oro.
South of the mission, there was a mesquite bosque, a dense shaded woodland of old trees, and people went into it the way people elsewhere went into a park. People had farmed that bottomland for at least two thousand years. The O’odham grew summer crops on the monsoon floods, letting the river spill out and lay down water and silt together. The Spanish arrived and added winter wheat, which needs irrigation, and cattle, which need stable banks.
The first Anglo farmers kept the Spanish pattern, with an irrigation master whose job was to divide the ditches fairly. It was a system built entirely on the assumption that the water would come to the surface on its own. After the ditch, it stopped doing that. In 1891, a University of Arizona professor reported that water could be pumped up from underground to irrigate the campus, and about that time the first local farm began running on pumped groundwater.
Every year the pumps got better. Every year the surface water mattered less, which felt like progress because it was. By 1913, the perennial flow past Tucson was finished. By 1940, pumping had pulled the water table so far down that the Santa Cruz only ran during floods.
That is the river Tucson would become famous for: a wide band of pale sand you could walk across in your shoes, dry three hundred days a year, with bridges over it that looked like a joke. Nobody in 1940 thought this was a crisis. Tucson had 36,000 people, a sanatorium economy, a university, an army airfield, and a very deep bank account it had barely touched. Underneath the Tucson basin and the Avra Valley next door sat something close to 70 million acre-feet of water in the top 1,200 feet of ground.
An acre-foot covers an acre a foot deep, about 326,000 gallons, and 70 million of them is a lake the size of a small sea, held in sand and gravel, invisible and almost entirely useless to anyone without a pump and a power bill. Tucson had both. In 1940, Tucson was taking around 50,000 acre-feet a year out of it. Nobody could see the level dropping.
Nobody was looking. Then on February 2, 1951, fifty-three minutes after the announcement was read out in Washington, bulldozers started moving dirt on a patch of creosote flats south of the Tucson Municipal Airport. Howard Hughes had bought 2,431 acres there in January. The Korean War was on.
The Air Force wanted the first radar-guided air-to-air missile in history built somewhere a long way from the Pacific coast, and Hughes Aircraft wanted the contract. Del Webb’s construction company put up the main building through 1951: Building 801, thirteen acres of floor under one roof, a single room you could lose a neighborhood in. It was in operation by December 16. On December 31, 1951, the plant and the land under it were deeded to the United States Air Force.
It became Air Force Plant 44, government-owned, Hughes-operated. Eleven months start to finish. It nearly went to Phoenix instead. The missile was the Falcon, and by 1960 the plant had built thirty thousand of them.
Employment went from nothing to 5,700 by 1957 in a city that had counted 45,454 residents at the 1950 census. One factory, one product, and thousands of households in a small desert town suddenly living off a federal contract. Every one of them needed water. Now here is the number everybody quotes about Tucson, and here is why it is partly a lie.
In 1950, the city counted 45,454 people. In 1960, it counted 212,892. That looks like the fastest growth in America, and in a sense it was. But more than 78 percent of the people inside Tucson city limits in 1960 were living on ground that had been annexed since the last census.
The city had not filled up. The city had grown a new edge and walked it outward over neighborhoods that were already there. Annexation does not create a single new person. What it creates is a customer.
Every time Tucson took in another square mile, it bought the little private water company that served it, welded the mains into its own system, and inherited the obligation to keep water in the pipes at pressure on an August afternoon. The population figure was partly a boundary. The water demand was entirely real, and it was arriving faster than anyone had planned for. By the summer of 1952, the two existing well fields north and south of downtown could not keep up.
On July 23, the Arizona Daily Star ran the headline, “More water is urgently needed. ” Underneath it, the city’s water superintendent, Phil J. Martin, Jr. , made the case with a line that shows exactly how Tucson thought about itself.
Living in desert country, the paper said, where a rain bucket on the roof wouldn’t provide more than a good shampoo, it is natural to wonder if the city can furnish enough water. The answer was a big yes if the voters approved $5. 5 million in water revenue bonds on August 12. They did.
And then Tucson went looking for somewhere to put the wells. It found a line on the map about eight miles south of downtown: old Nogales Highway below Valencia Road, running along the edge of the San Xavier district of what was then called the Papago Reservation. Between 1954 and 1968, the city drilled there and bought private wells there until it had thirty-four of them in a row. They called it the Santa Cruz Wellfield, named after the river whose buried water they were pulling up.
Fifteen of them were still pumping forty years later. In 1954, nobody involved thought they were doing anything unusual. Tucson had drilled wells east of San Xavier since 1881, when a private company put the first ones in, and the field had simply grown outward with the town for seventy years. That is the honest version, and it is well documented: adjacency and nothing else.
The other version came later from the people who lived on the other side of the line. The San Xavier District’s own position, stated in a formal comment letter filed with the Federal Bureau of Reclamation in March 2026, is that the city of Tucson deliberately built its wellfield along the eastern boundary of the reservation, knowing the pumping would drain the water table underneath it. No independent source has been found that supports the deliberateness, or that anyone at the time foresaw it. What the record settles is the outcome.
A community which had farmed that bottomland for two thousand years lost the water under it inside one human lifetime to a legal doctrine holding that the water belonged to whoever could lift it. Nobody broke a law. The great mesquite bosque south of San Xavier Mission, the one that had shaded that bottomland since before any of this, died in the 1950s. The trees did not burn or get cut.
The water table simply fell below their roots, and they stood there and finished dying over a few years, and then they were firewood. Subsistence O’odham farming largely stopped in the 1950s when allottees began leasing their ground to non-O’odham growers because they no longer had the water to work it themselves. By 1975, new wells drilled on the district were coming up dry. Not low, dry, hitting bedrock with nothing above it.
Meanwhile, water levels measured by the University of Arizona had fallen more than two hundred feet in parts of Tucson’s central wellfield and more than one hundred feet in its southside wellfield. There was one more party on that ground, and it arrived with a checkbook and a drilling rig. In April 1957, the Department of the Interior’s Papago Indian Agency advertised a competitive sale of exclusive prospecting permits with options to lease over 142 individually owned allotments and 160 acres of tribal land at San Xavier. The ground was cut into three tracts of roughly 5,120 acres each.
It sat on the northern end of a copper belt that the American Smelting and Refining Company had already traced coming up out of its Mission ground to the south. ASARCO bid on all three tracts and won all three. The bonuses it paid are on the record in federal court: $283,000 for Tract 1, $757,222 for Tract 2, and $26,051 for Tract 3, a little over a million dollars altogether, handed to the superintendent at Sells and credited to the individual Indian money accounts of the allottees at a flat rate per acre, the same rate for every man, whatever happened to lie under his own ground. Drilling began on September 14, 1957.
The first holes found ore that September and October. Then came the part that shows what the transaction actually was. In 1959, the company exercised its options on 560 acres in Tract 1 and 1,994 acres in Tract 2 and walked away from the rest. ASARCO had bought the right to look at 15,360 acres and had taken a lease on about 2,554 of them.
That is how mineral exploration works, and there is nothing improper in it. What the company did next is less ordinary. It took the money it had paid for the ground it gave back, $888,583 once surveying and drilling were added in, and deducted it from its 1959 federal income tax as a loss. The Commissioner of Internal Revenue disallowed most of it.
ASARCO paid the assessment, sued for a refund of $680,513, and in 1970, the Court of Claims ruled in the company’s favor. Read that order of events again because the order is the whole point. The federal government, acting as trustee for several hundred O’odham landowners, ran the auction that put a copper company onto their allotments. It deposited the proceeds in accounts it controlled on their behalf.
And eleven years later it lost a lawsuit to that same company over whether the payment could be written off against tax. The Mission Mine went into development in 1958, began stripping in 1959, reached commercial production in 1961, and is still there, an open pit working rock at about two-thirds of one percent copper, moving fifteen to twenty thousand tons a day. It has never stopped. Every ton of that drank water, pumped up out of the same basin, carried away from the land it came out of and never returned to it.
By the early 1970s, the mining companies working the upper Santa Cruz, ASARCO, Duval, Pima Mining, Anaconda, Amax, were taking around 25,000 acre-feet a year out of one small critical groundwater area and moving all of it somewhere else. Which brings us to the farmer and to the strangest lawsuit in the history of American water. His name was R. Keith Walden.
In 1948, he moved his Farmers Investment Company out of California, bought the Continental Farm south of Tucson, and started growing cotton on the flat ground beside the Santa Cruz. He worried in the 1950s that synthetic fibers would kill the cotton market, so he began converting to pecans. A pecan takes ten years to bear and a great deal of water. It is a bet on staying.
Walden ended up farming roughly 7,000 irrigated acres and running what became the largest pecan orchard on Earth. It still is. On November 24, 1969, FICO filed suit. The defendants were the mines: Anaconda, Amax, their partnership Anamax, Pima Mining, Duval, and American Smelting and Refining.
The complaint said the mines had bought well sites inside the Sahuarita-Continental Critical Groundwater Area, an area the state land department had designated back in October 1954, and were pumping water out of it onto land somewhere else. FICO itself was pumping about 38,500 acre-feet a year. Its neighbors took another 15,000. The mines took 25,000.
Recharge was a fraction of the total. Everybody agreed the water table was falling. FICO said that if this continued, the water under its orchards would be gone or too deep to lift, the land would go back to bare desert, and the damage would run past $50 million. Then Andrew L.
Bettwy, the Arizona State Land Commissioner, was added as a defendant. And then the city of Tucson walked into the case voluntarily as an intervenor on its own initiative, which turned out to be the single worst decision in the whole affair. Tucson intervened because it had already lost this argument once. In December 1968, a farmer named W.
W. Jarvis went to the Arizona Supreme Court on behalf of himself and everyone else cultivating 33,000 acres in the Avra and Altar valleys, the long basin on the far side of the Tucson Mountains. Their complaint was simple. The city of Tucson had drilled six wells out there more than fifteen miles from its customers and was preparing to pipe the water over the mountains into town.
The valley was inside the Avra Valley critical groundwater area, which by statute meant there was not enough water in it for the farms already there. In 1969, the court agreed. Then came five words a growing city never wants in a published opinion: “Tucson’s action is clearly illegal. ”
The injunction was severe.
The state land commissioner was ordered to cancel the rights of way across state land, which meant the pipeline had nowhere to go. What happened on December 28, 1970 changed the map of southern Arizona, and it is the hinge of this entire story. The court did not reverse itself. It found a door.
Arizona statute ranked water uses in a fixed order: domestic and municipal first, irrigation and stock second. The justices took that ranking as a statement of policy. “The creation of such a priority clearly evidences a legislative policy that the needs of agriculture give way to the needs of municipalities. ” Then the operative sentence: the decree would be modified if Tucson purchased or acquired title to cultivated land in the Avra and Altar valleys and used the water that would have gone on those fields to supply its municipal customers.
Tucson could withdraw an amount equal to the annual historical maximum use on the land it bought. The Arizona Supreme Court had just told a city how to legally drain a valley. Buy the farm, retire the farm, take the farm’s water. It is not an accusation.
It is the holding. So Tucson went shopping, and it went west over the ridge away from the Santa Cruz altogether. Through the late 1960s and into the early 1980s, it bought Avra Valley Farms, over 21,000 acres for something close to $23 million. That is roughly $1,000 an acre.
In the mid-1970s, $1,000 bought a used car with some life left in it. Tucson was paying a used car per acre for land, the wells on it, and the water under it in perpetuity, and then taking the crops out and letting the fields go back to creosote. If your grandfather farmed cotton out there, the city bought his wells, his fields, and everything under them, and the fields are bare creosote now. It was entirely legal, entirely court-sanctioned, and entirely quiet.
The farmers who sold took the money, and the ones who did not sell watched the water table under their remaining fields keep dropping. Because in a common pool, the neighbor who quits farming does not stop pumping. He pumps harder for a city. On August 26, 1976, the Arizona Supreme Court handed down Farmers Investment Company v.
Bettwy, and it is worth being precise about what it said because almost every short account of it gets something wrong. First, Bettwy was not a company. Andrew L. Bettwy was a man, the Arizona State Land Commissioner, sued in that capacity and added to the case years after it started.
Second, the fight was not about moving water out of the basin. It was about moving water off the parcel. The holding runs: “Water may not be pumped from one parcel and transported to another just because both overlie the common source of supply, if the plaintiff’s lands or wells upon his lands thereby suffer injury or damage. ”
That sentence, in a state with no groundwater law, was an earthquake.
It meant that across Arizona, every pump that lifted water on one piece of ground and delivered it somewhere else was suddenly exposed. Every mine, every city, every water company in the state. FICO, though, did not walk out of that courtroom with an injunction in its hand. It won the rule and went back down to the trial court to prove its damages.
The only injunction the Supreme Court actually affirmed that day was against the city of Tucson. The lower court had frozen the city’s pumping in the Sahuarita-Continental subdivision at whatever rate it had been running before April 12, 1972, and barred it from using any well drilled there after that date to send water anywhere outside the subdivision. The justices affirmed it in a single sentence. Think about what that meant on a Friday afternoon in Tucson in 1976.
Pima County held nearly 200,000 more people than it had in 1960. It had a freeze on one of its southern sources and a court-written formula limiting the western one to what the retired farms used to grow. Every direction was now a lawsuit. The dissent is the part worth hearing out loud.
Chief Justice Cameron wrote that under existing law, two adjacent landowners could pump each other dry. Access to water, he said, was determined “not by reasonable use but by a race for consumption controlled by the physical ability to extract it from the common supply. The larger and deeper the well, the more powerful the pump, the more likely a generous amount would be available on the land that pump served, while the water underlying the neighbor’s land is sucked down below the depth of his well. ” And then the line that sums up sixty years of Arizona: “To the small or family farmer, the right to water becomes a cruel illusion proclaimed by law but unobtainable in practice.
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One more name on that case, and it is the name that makes the rest of the story fit together. Arguing for the state of Arizona was Attorney General Bruce E. Babbitt. Remember him.
Within two years, he would be governor, and he would be the one who pulled the pin. But before any of that, Tucson tore itself apart over a water bill. By the mid-1970s, a majority on the Tucson City Council belonged to what was then called the controlled growth movement. They inherited a utility in trouble.
Distribution mains had been thrown outward through the early 1970s to keep up with subdivisions, the summer of 1974 had nearly outrun the system’s capacity, and rates set years earlier were not covering the cost of delivery. The new rates adopted in June 1976 averaged about 22 percent more. What blew the roof off was one component of them. Tucson had grown uphill, off the floor of the Santa Cruz Valley and into the foothills of the Catalinas.
Water does not flow uphill for free. It has to be pumped, and pumping costs electricity. So the city divided itself into 79 elevation zones, each 100 feet of rise, and charged 20 cents per 100 cubic feet for every zone the water had to climb. Engineers call it a lift charge.
Everyone else called it something less printable. The bills landed in July. For customers in the high zones, they had quadrupled in a month. For plenty of others, they had doubled.
And here is the reversal that decided Tucson’s next thirty years. The rate increase was widely believed to be a growth control measure, a deliberate squeeze on the foothills to discourage building up the hillsides. It was not. The money was going into pipes and reservoirs and new supply to serve exactly the growth the protesters wanted.
The people who organized the revolt were the pro-growth, pro-canal side of town, and they were revolting against an increase designed to pay for growth. The council rescinded the lift charge in August and kept the rest of the increase. It did not matter. On January 18, 1977, in the first recall election in the history of Tucson, three council members were thrown out of office.
Tucson had never recalled anybody before. Their replacements discovered what the rates had actually been for, kept the new structure, and raised them again. That is the joke history plays on cities. But the lesson Tucson drew was not about rates at all.
It was about survival. Ever since, council members and water staff have handled water pricing the way you handle a wasp in the car. And two words still end an argument at city hall: “Remember the recall. ”
The most powerful tool a desert city has for controlling demand, making water cost what it costs, had just been taken off the table by the voters themselves.
So the city reached for the only other tool. It asked people nicely. Toward the end of the decade, Tucson Water launched “Beat the Peak,” built around a cartoon roadrunner called Pete the Beak, whose entire message was to stay off the system between 4 and 8 in the evening. It was aimed at the peak, not at total use, at delaying the next set of mains and reservoirs.
It worked far better than that. Meanwhile, the lawsuit nobody in Tucson wanted to think about was sitting in federal court. In February 1975, the United States, acting on behalf of the Tohono O’odham Nation, sued the state of Arizona, the city of Tucson, Farmers Investment Company, ASARCO, and the other mining companies. The claim was that excessive pumping had damaged the tribe’s water rights.
The case would have forced a federal court to decide whether the Winters doctrine, the rule that creating a reservation reserves the water needed to make it livable, reaches water under the ground, not just water in rivers. Nobody knew the answer. Everybody understood what the answer could cost. The Arizona Daily Star put the fear plainly in an editorial at the time: “More than a century of government failure to preserve the Papago interests assured the tribe a court victory.
And victory could have meant the permanent shutdown of mines and farms and an end to city growth and development. ” That was almost certainly too dark. It did not have to be true to work. A bond rating does not wait.
So everyone negotiated. And in the negotiating, the non-Indian parties found something useful. If Colorado River water was what it would take to settle with the O’odham, then Washington had a new reason to finish the canal to Tucson. The tribe’s claim, which had terrified the city, became one of the arguments for building the thing that would rescue it.
On October 12, 1982, President Reagan signed the Southern Arizona Water Rights Settlement Act. San Xavier was to get 27,000 acre-feet a year of Central Arizona Project water and 23,000 of reclaimed water, 50,000 in all. The Schuk Toak district was to get 10,800 and 5,200, for 16,000. Sixty-six thousand acre-feet a year altogether, of which 37,800 was canal water.
And it came with conditions that tell you exactly who was negotiating from strength. The canal water only flowed if the nation accepted a cap on its own pumping beneath San Xavier of no more than 10,000 acre-feet a year. The reclaimed half depended on Tucson agreeing to supply it within a year. That dependency jammed the whole settlement for twenty-two years, until a second act in 2004 moved the second trench onto canal water instead.
The numbers never changed. The delivery just kept not happening. The state legislature, meanwhile, had a decision from its own Supreme Court sitting in its lap, and it did not take long to answer it. Bettwy was never overturned.
It was legislated around inside a few months. In 1977, the legislature passed certificates of exemption, which let anyone already transporting groundwater out of a critical area go right on doing it. The rule that had shaken every pump in Arizona was neutralized by a clerk’s form. It took eight months.
But something else happened in 1977 as well. That same year, the legislature created a commission to study comprehensive groundwater management, two full years before any federal threat. The threat came anyway, and it was theatrical. President Carter’s interior secretary, Cecil Andrus, announced that unless Arizona produced a serious groundwater law, he would personally stop the Central Arizona Project.
Behind the announcement was Arizona’s own governor, Bruce Babbitt, the same Bruce Babbitt who three years earlier had argued for the state in the FICO case, privately urging Andrus to make exactly that threat against his own state. It worked because it had somewhere to land. Babbitt convened what everyone involved called the Rump Group, representatives of mining, agriculture, and the cities, meeting behind closed doors. What came out was handed to the legislature and passed without a single amendment in a seven-hour session.
Babbitt signed the Groundwater Management Act on June 12, 1980. The act created the Department of Water Resources, made every large pumper report what it took, required a developer to prove an assured one-hundred-year water supply before selling a single lot, and set a goal for the Tucson and Phoenix areas of safe yield by 2025, no more out than in. It was and still is the most serious groundwater law any western state has written. It also did something quieter.
By fixing everybody’s rights in place, it made the city’s position permanent. Tucson’s growth was no longer illegal. It was licensed. And then, on a weekend at the start of October 1983, the river came back.
The remains of Tropical Storm Octave stalled over southern Arizona and dropped six and a half to seven and a half inches of rain across the Tucson basin in five days. The Santa Cruz, dry three hundred days a year, ran higher than it had in the entire instrumental record, peak flows more than twice anything measured in sixty-five years. On the morning of Monday, October 3, one of the eighteen bridges over the river was open. Power was out to more than 20,000 homes and businesses.
Four people died. Damage to public infrastructure in Pima County came to $64 million. And across southeastern Arizona, the bill reached $370 million. Here is the part that closes a circle opened ninety-four years earlier.
The reason that flood was so destructive is that the Santa Cruz no longer had a floodplain to spread out on. It had a trench, the one Sam Hughes’s ditch started in 1889, deepened by every flood since and by a water table that kept dropping out from under the banks. A river in a trench does not slow down. It scours sideways and takes the bank and the houses and roads on the bank with it.
So Pima County rebuilt the banks in soil cement. It worked. It also finished the job. The Santa Cruz through downtown Tucson is now a straight-sided channel that cannot meander, cannot rebuild a bed of sediment, and cannot grow a cottonwood forest even if you put water in it.
Which is exactly what was about to arrive. The Central Arizona Project is one of the largest things Americans have ever built for a single purpose. Congress approved it in 1968. It runs 336 miles from the Colorado River at Lake Havasu east across the state to Phoenix, and then south to Tucson.
And because the desert rises the whole way, fourteen pumping plants lift the water 2,400 feet uphill before it gets there. It cost about $4 billion. It reached the Tucson area at the end of the 1980s, and the city planned its arrival like a coronation. Delivery started in November 1992 to roughly 84,000 homes, about 58 percent of the connections Tucson Water served.
Within days, the complaints started, and they did not sound like complaints about taste. The new water was chemically different enough to strip the old sealed layer of corrosion off the inside of aging galvanized steel mains, and it carried the rust to the tap. Water came out red, then orange, then yellow, then brown. Pipes burst.
Water heaters and evaporative coolers failed. People reported skin rashes, ruined laundry, dead plants, dead aquarium fish, damaged pools, and in some houses standing water through the floor. If you grew up in Tucson, you grew up drinking water that had been underground since before the mission was built, out of a tap cold and famously good. In November 1992, you turned the same tap and it came out the color of rust.
Households switched to the canal increased their bottled water buying more than tenfold. The utility chased the chemistry. It added a corrosion inhibitor, then found it could not keep the dose even across a system that big. It adjusted pH repeatedly, and those frequent swings were later identified as probably making the problem worse rather than better.
In October 1993, the city cut off the worst-hit east side of the delivery area. In November 1994, all canal water had to stop anyway so the project could repair its siphons. And when the time came to turn it back on, the council voted not to. That was the end of it.
By then, the head of Tucson Water and the manager of the treatment plant had both resigned, and a utility that had been one of the most respected in the West had lost its city. On the ballot in November 1995 came the Water Consumer Protection Act. It said the city could not put Colorado River water directly into anybody’s house unless it was treated to the quality of Avra Valley groundwater and carried no disinfection byproducts, which in practice meant not at all. About 41,000 people voted for it, 56 percent.
Two years later, a measure to repeal or gut it was defeated too. Read that plainly. A desert city, having spent four billion federal dollars and forty years of political capital to get a river brought to it over a mountain range, voted twice to refuse to drink it. Then on November 2, 1999, Tucson settled the other question.
Proposition 200 would have extended the ban and tied new water connections to proven supply, a hard cap on growth written into the city code. Business interests put more than $700,000 into defeating it. Nearly every elected official in the region opposed it. It lost 72 to 28.
Tucson had voted not to drink the canal and then voted four times as emphatically not to stop growing, which left exactly one answer, and it was the one the whole century had been pointing at. If the city could not put canal water in the pipes, it would put canal water in the ground. Out in the Avra Valley, on the retired farmland Tucson had been buying since the Supreme Court told it to in 1970, the utility built shallow basins and let Colorado River water soak down into the aquifer: eleven basins over 317 acres at the central Avra Valley project, nine more over 226 acres to the south. Months later, it pumped the same water back out through wells filtered by a few hundred feet of sand, chemically indistinguishable from the groundwater Tucsonans had always had.
It is the most expensive way imaginable to deliver water. And it is the reason Tucson now recharges nearly all of its 144,191 acre-foot annual allocation instead of drinking it directly. And the aquifer began to come back. Across the upper Santa Cruz basin, forty-eight monitoring wells averaged a rise of about fourteen inches a year from 2000 to 2020.
Under downtown, the water table has come up more than one hundred feet. At Speedway and Swan, it is up nearly fifty. One well less than a mile from the southern recharge basins in the Avra Valley has risen twenty-eight feet since 2000 into ground that a mining company, a pecan farmer, and a city had spent forty years emptying. The basin is not saved.
The federal government declared a Tier 2 shortage on the Colorado for 2023, and every foot of that recovery is borrowed from a river seven states are fighting over. But the water is rising. And it is rising because the taking finally moved somewhere else. Since 2019, there has been water in the Santa Cruz again through downtown Tucson: about a mile of it released from a treatment plant running between the gray soil-cement banks the flood of 1983 built.
Fish have turned up in it. Nine miles south, below the white towers of San Xavier, the same river is still a trench thirty feet deep, dry, exactly where Sam Hughes’s ditch put it in the autumn of 1889.