The Salt River and Canals

The Salt River has many names: Onk Akimel in O’odham (Pima); Va Shly'ay in Maricopa; Rio Salado in Spanish. It has long nurtured people with irrigable land in the Sonoran Desert. In many ways, the river has kept the lands it flows through habitable despite the region’s arid climate. The Salt River Valley is the main area with canals that branch from the river east to west through Phoenix (and its adjacent municipalities) from Granite Reef Dam in East Mesa to the confluence of the Gila and Salt rivers in Avondale. The river spans a distance of nearly 50 miles across the Salt River Valley, and the canal network extends its water throughout.

Many more miles upstream from the city, the Roosevelt Dam holds a lake of water before the Salt River Canyon and Apache Trail that leads to the Salt River Valley. A significant extent of water could flow, yet it is metered through a series of flood-controlling dams and distributed into canals in the Phoenix metropolitan area. If the river was not metered it would eventually flow onto the Gila River to merge with the Colorado River at Yuma and on to the Gulf of California. In the Phoenix metropolitan area, the network of over 1,000 miles of canals was begun by Hohokam/Huhugam cultures between 100 to 1450 CE, and they have been continuously flowing since. Architecture along the canals in Phoenix range from earliest sites, like S’edav Va’aki (Pueblo Grande) to a twenty-first-century building with a canal forming its courtyard, Interdisciplinary Science and Technology Building 7 (ISTB7) at Arizona State University in Tempe.

Over a thousand years ago, Hohokam/Huhugam engineers set a series of canals into motion for irrigating the Salt River Valley. Indigenous architects adapted many forms for living in the Salt River Valley. Prehistoric houses and communities, such as Casa Grande, S’edav Va’aki, and Loma Del Rio, are the original dwellings in the region. At these sites in or near Phoenix are mound platforms, partial earthen walls, and rounded edged ball courts that have survived many centuries. Further upstream, in the much less populated areas of the Upper Salt and in the Salt River Canyon, is more Hohokam architecture of cave and cliff dwellings.

In more recent history, Indigenous communities along the Salt River have devised many ways of adapting to desert life. For example, there are adobe block houses, brush houses, jacal houses, ramadas, round houses, wickiups, and windbreaks, among other strategies for living in extreme climate region. The intense sunlight and scarcity of materials has generated an enormous variety of architectural form through individual and cultural ingenuity and resilience.

Accounts by the Spanish show both admiration and conflict in the Salt River region, as was also the case in nineteenth-century United States. In Arizona’s territorial years, the Salt River witnessed much bloodshed in terrible fighting, such as the 1872 Battle of the Salt River Canyon (or Skeleton Cave). Besides military campaigns, commissions such as the Hemenway Expedition (1886–1896) went to the Salt River Valley and noted scientists documented their ethnographic investigations or archaeological observations. Others sought wealth through mining or industries during Arizona’s territorial years. While many of the canal paths were first made by the Hohokam, expanding on the idea and the network, the northernmost Arizona Canal was a new branch at the time (under construction in 1900). President Theodore Roosevelt helped commission what would become a namesake dam but was originally called Salt River Dam No. 1 when it became operational on March 18, 1911. The dam was constructed with cyclopean masonry, quarried from nearby canyons and finished with concrete. It was an early electricity source for much of the region.

On February 14, 1912, Arizona become a US state. Publications and advertisements around the time of statehood show abundance in agriculture, growing industry, investments in property, and fortunes to be made. Much of the valley of Phoenix was agricultural land nourished by the Salt River canals.[1] Early-twentieth-century scenes of canal irrigation ranged from peaceful, charming, and quiet to busy and industrious. Around this time, maps show both regular gridded streets and the irregular delicate arteries of the canals. Besides the grid and the canals, the Omar Turney c.1922 map also shows the locations of Pueblo communities.

Further into the twentieth century, the Salt River Valley witnessed unprecedented and overwhelming growth with demands on life-sustaining infrastructure such as the waterways, but also increased convenience infrastructure for vehicular transportation and electrical power. Development in Phoenix took a sharp turn from agricultural and ranching lands to expansive suburban real estate. To support this, the US Army Corps of Engineers and a utility company called the Salt River Project bolstered and maintained water infrastructure.

Several hydroelectric stations of different magnitudes were installed along the Salt River and canals. Roosevelt Dam currently generates 36 MW and holds back a 1.6 million-acre-foot lake upstream. Between Phoenix and Scottsdale, the Crosscut Powerplant once generated 3,000 KW of power. In Scottsdale, Arizona Falls is a small-scale hydroelectric plant that generates 750 KW of power for 150 residences. Flooding was a perennial issue, and with their installation, the dams also provided a measure of flood control that mitigated what were once seasonally damaging floods.

After midcentury, founding dean James Elmore led the architecture program at Arizona State University in ambitious plans for the Salt River and the canals. The Rio Salado Project began in 1966, and at first many designs remained on the drawing boards.[2] One of the most ambitious was a proposal to channel and fill water throughout the many miles along the Salt River’s path to the Gulf of California, allowing shipping along the river from Puerto Pinasco to an inland port in Tempe. Plans such as these sparked the students’ imagination, and Elmore’s initiative led to generations of trained architects with the local design and planning framework of Rio Salado in mind. Through the end of the twentieth century, the Salt River developed issues that residents and architects endeavored to address. Much of the riverbed had dried and sections were either used for mining or landfill, or were deserted entirely. The public sought improvements beyond utility and industry. Designers supplied various amenities, parks, places for recreation, and areas of restored nature.

In the 1980s and 1990s, PBS Arizona covered the ups and downs of Salt River improvements regularly in their program Horizon. There were many controversies surrounding taxes, property values, funding, gentrification, and water use, among others. Groups such as Concerned Citizens Against Rio Salado opposed the proposed improvements. The 1987 proposal to improve the Salt River was turned down countywide on November 3, while Tempe approved it. Advocates persisted and the US Army Corps of Engineers became involved in planning, since the project would be federally funded. In a 1995 episode of Horizon, another Arizona State University Dean of Architecture, John Meunier, likened the opportunity to improve the river to building medieval cathedrals, in their extended time frame and high level of community involvement. Meaner described the need for environmental rehabilitation, and the foreseen needs not just for Tempe, who approved the plan, but especially for Phoenix, to improve its center and avoid the suburban sprawl that had become linked with its reputation.

Historically, the primary function of the Salt River canals was distributing water for agriculture. Unlike canals in Venice or St. Petersburg, they are not used for transportation by boat, except at lakes along the Salt River, such as the two-mile-long Tempe Town Lake. The Tempe Lake as well as the upstream lakes are areas where the water is used for many purposes including recreation. At Tempe Lake, one can enjoy sailing, rowing, and paddleboarding with a backdrop of Papago Park rocks, “A” Mountain, and the glassy office buildings that line the lake. The signature architectural work of Tempe Lake’s development in the early-twenty-first-century is Tempe Center for the Arts (2007, Architekton). As time passed, the canals’ purpose has shifted from agricultural irrigation to extension of valuable waterfront.

As of 2023, the Salt River Project utility company maintains nine main aboveground canals and hundreds of lateral canals that form a network of over a thousand miles. Many of the canals are lined with paths for bikes, walking, or running. The Salt River Project also commissioned art to line the embankments, such as along Crosscut Canal. There are many bridges, especially on the Scottsdale Waterfront along the Arizona Canal. Some canals even allow fishing; bass, carp, catfish, and other species are stocked in Tempe Town Lake, and can be caught. The Salt River Project introduces fish to eat vegetation and help clean the canals.

One pocket of revitalized Salt River, on Central Avenue in the heart of Phoenix, is the Rio Salado Audubon Center (2009, Weddle Gilmore Architects). There is enough water brought back to the river for riparian birdwatching. River rock housings for endangered burrowing owls can also be found in the landscape around this area around the Phoenix Sky Harbor International Airport. The zone of the Salt River by the airport has been kept drier than other zones, in an effort intended to discourage types of avian habitat from interfering with flight paths. That area does include a facility called Liberty Wildlife, a rescue shelter for animals designed with sustainable architecture.

The Salt River has become a planning framework stemming from continued needs and interests of the population. Collections and exhibitions at museums such as the Huhugam Heritage Center, S’edav Va’aki (formerly Pueblo Grande Museum), wildlife centers such as Audubon and Liberty, economic developments such as Tempe Lake, and canal cultural events such as Canal Convergence demonstrate the continued importance of the canals to the communities of Phoenix metropolitan area, as well as those up and down stream along the Salt River. Canal Convergence is an annual event that draws many people to the Scottsdale Waterfront. The event was founded in 2012, with predecessor festivals hosted by Salt River Project, City of Scottsdale, and its public art programs. It is an annual November event in the vicinity of the Marshall Way Bridge (2007, John Douglas Architect) and the Soleri Bridge (2010, Paolo Soleri Architect) in the center of Scottsdale.

Many of the original routes of the Hohokam/Huhugam canals remain in use in the twenty-first century and have been updated. At Arizona State University’s ISTB7, a canal flows through a courtyard for the new building, creating a reflective space with the quiet sound of moving water next to one of Tempe’s busiest intersections.

From the Indigenous engineers who began the system of Salt River canals to the urban river’s status in the present day, water has been and always will be precious in the Sonoran Desert. The Salt River and its canal infrastructure have been in vital for over a thousand years in securing water for Phoenix’s ever-changing population.