The History of Water and Water Filtration in Phoenix - Part 1
Water has always been the lifeblood of our community in the Valley of the Sun. From the days when the Hohokam tribe was busy digging canals to keep their crops alive, all the way to the modern filtration systems that ensure your tap water is crystal clear, our community has always relied on our ability to capture, store, and purify water.
The Aussie Plumber podcast is releasing an exclusive three-part series that helps understand the present by looking back into the history of water and water filtration in Phoenix.
Episode 1 of 3 - The History of Water and Water Filtration in Phoenix
In The Aussie Plumber Podcast's first of three episodes in this series, we trace Phoenix’s earliest attempts to secure water—from the ingenuity of the Hohokam canals to Jack Swilling’s 1868 ditch that brought new life to the Salt River Valley. It’s the foundation of the story that follows: how a desert city learned, sometimes the hard way, that survival depends on capturing, storing, and treating every drop.
Phoenix Before Modern Dams: Ancient Canals and Early Irrigation
Long ago, before the city of Phoenix had its current name, a clever group of people called the Hohokam built a huge maze of canals across the big, flat lands where the Salt and Gila Rivers would flood. The canals they made were more than 300 miles long altogether! The Hohokam dug these canals by hand, making them very straight and smooth so that water could flow through them easily without needing any machines. This was amazing work in a place where it gets very hot in the summer and there isn't much rain.
For a long time, the Hohokam farmers kept the canals clean and strong, getting rid of any dirt and fixing the sides of the canals when they needed it. They did this so they could grow their favorite foods like corn, beans, and squash in a place where nothing had ever grown before. It was hard work, but they made it possible for their people to live in a place that seemed too dry and hot for farming.
By the mid-1800s, those ancient earthworks lay abandoned but visible as faint scars on the desert floor. In 1868, prospector Jack Swilling saw their potential and rallied local settlers to clear and extend the old Hohokam routes. His project, soon dubbed “Swilling’s Ditch,” delivered year-round water to newly laid wheat and barley fields along the Salt River. What began as a makeshift irrigation ditch would evolve into the backbone of Phoenix’s first farming community—and prove to skeptics that the desert could sustain settlement with smart water management.
The Floods and the Farmers’ Turning Point
In late spring of 1891, three days of torrential downpours transformed the normally tranquil Salt River into a roaring torrent. Levees gave way, fields turned to lakes, and dozens of farms along the riverbank vanished under floodwaters. Cattle, crops, and homes were swept away in hours—only to be followed months later by crippling drought that left once-fertile soil parched and cracked.
Over the next decade, this cruel pendulum of inundation and thirst became the Valley’s defining curse. One season, water gushed uncontrollably through makeshift earthen dikes; the next, farmers watched irrigation canals run dry while orchards withered in the desert heat. Individually, homesteaders had no leverage—each risked ruin any time the river swelled or subsided.
Faced with this uncertainty, a group of forward-thinking settlers met on April 11, 1903, in Tempe’s one-room schoolhouse. Together, they founded the Salt River Valley Water Users Association—the nation’s first collective, member-funded irrigation district. By pooling assessments on each irrigated acre, they secured federal backing under the Reclamation Act of 1902. Their cooperative vision would soon finance construction of Roosevelt Dam and give birth to today’s Salt River Project, the agency that still allocates, stores, and delivers water to more than two million Valley residents.
Roosevelt Dam: Engineering the Desert’s First Breakthrough
Between 1906 and 1911, the U.S. Reclamation Service transformed a rugged Salt River canyon into Phoenix’s first major reservoir. Rising 280 feet above the riverbed and spanning 1,350 feet from rim to rim, Roosevelt Dam was conceived with two unmistakable goals: to tame the Salt River’s destructive spring floods and to guarantee year-round irrigation for the Salt River Valley’s fledgling farms.
Downstream from where the river's force was harnessed, engineers sculpted a series of shallow pools, like little lakes of concrete. Here, the rushing water would slow its frantic pace, giving the heavier particles a chance to settle at the bottom. It was like the river was taking a deep breath after a long run.
The Roosevelt Dam quietly worked behind the scenes to ensure water security for Phoenix and the surrounding areas. It doesn't have fancy turbines like Hoover Dam, but it does something just as important - it stores water and provides irrigation to the dry, arid landscape.
The Rapid Growth of Phoenix in the 1920s to 1940s
Between 1911 and 1920, Phoenix’s population soared from just over 11,000 to more than 28,000 residents—a remarkable doubling that transformed a dusty frontier settlement into a burgeoning desert city. So Phoenix started booming, with houses popping up everywhere, farms spreading out into the valleys, and businesses wanting reliable water to keep things going.
But this rapid growth exposed Phoenix's fragility. floodwaters from Cave Creek washed away fields, roads, and simple homes. And speaking of Cave Creek, in 1923, concerned locals came together to build an earthen dam on Cave Creek. Though small, its 32-foot-high crest protected farmers' livelihoods on the city's outskirts and set a precedent for managing water on a larger scale.
As the Great Depression gripped the nation, New Deal programs redirected federal dollars into Arizona’s infrastructure. Between 1936 and 1939, the Bureau of Reclamation raised Bartlett Dam on the Verde River, doubling Valley storage capacity and laying miles of steel‐ribbon transmission mains into Phoenix proper. For the first time, treated water flowed under pressure through city neighborhoods—replacing private wells with a coordinated municipal network.
These projects did more than safeguard farms or reduce flood risk; they engineered the reliable delivery and basic treatment standards that Northeast Phoenix and Arcadia homeowners enjoy today.
The First Modern Water Treatment Plant (1949)
In 1949, Phoenix unveiled its first state-of-the-art water treatment plant, the Verde Water Treatment Plant. Before Verde, Phoenix residents had to make do with murky, smelly water that sometimes made them sick. But Verde brought a whole new level of clean water in Phoenix. It used a two-step process to purify the water from the Salt River canal.
First, the water flowed through special sand filters. These filters were like giant sandboxes, but they trapped all the tiny particles and dirt in the water. Next, the water went into a chlorine chamber. Just like how chlorine keeps your pool clean, it also kills germs in drinking water. The Verde plant carefully added just the right amount of chlorine to make the water safe for everyone to drink.
When the city decommissioned the Verde Water Treatment Plant in 2011—transferring its duties to larger, more efficient treatment plants—the blueprint it established endured. The way it purified water became the standard for all of Phoenix's water treatment plants.
Preview: Episode 2 of The History of Water and Water Filtration in Phoenix
In the next episode, we're going to talk about how Phoenix built these massive water treatment plants all across the Valley - from Maryvale in the west to Alhambra up north. We also built this huge aqueduct called the Central Arizona Project, which brings Colorado River water right down to Arizona. It's pretty impressive, actually!
Subscribe to the Aussie Plumber Podcast, bookmark this series, and tune in for Part 2 as James “The Aussie Plumber” Hill uncovers the mid-century breakthroughs—and emerging challenges—that continue to shape your home’s water quality.
