Some 4,000 years ago, ancestors of the Hohokam people settled at the base of (what is now known as) Tucson’s A Mountain on the banks of the Santa Cruz river. At that time, the river flowed year-round and supported lush woodlands of cottonwood, willow, and mesquite. These people created an extensive system of irrigation canals, supporting an agricultural society that lasted thousands of years. Spanish explorers came to the area in the 1600s, followed by Anglo immigrants in the 1800s; all depended on the river for farming, drinking, and even fishing. However, by the 1940s, as Tucson grew, a combination of groundwater pumping, surface water diversions, and erosion left the channel of the Santa Cruz River dry.
This summer, the City of Tucson and Tucson Water will reintroduce a ribbon of flowing water to this part of the Santa Cruz River to both make better use of our water resources, and to revive a bit of the river’s former beauty and vitality. The effort is known as the Santa Cruz River Heritage Project, and the target launch date is June 24, El Día de San Juan — the traditional start of the summer monsoon season and the birthday of the patron saint of water. On that day, Tucson Water will begin releasing up to 2.8 million gallons of reclaimed water every day into the Santa Cruz River, in an area just south of A Mountain and Downtown Tucson.
Reclaimed water is highly treated wastewater that Tucson Water has provided since 1984 to irrigate parks, schools, golf courses, and neighborhood landscapes to conserve drinking water. Today, reclaimed water represents about 10 percent of our water resources. However, about half of Tucson Water’s reclaimed water is not used by customers but discharged into the Santa Cruz River further downstream, near the city’s northwestern edge. The location of this discharge causes Tucson Water to lose physical and legal control of this valuable resource. The Heritage Project involves using our existing reclaimed water pipes to discharge some of this water further upstream, where it will percolate into the riverbed and enter the aquifer.
Tucson Water hydrologists expect that the water will flow up to about a mile before it all percolates into the ground. This stretch of perennial flow will support native vegetation, which will, in turn, attract wildlife. People will have easy access to the site through the existing bike and pedestrian trails on both banks of the river. The project will complement the thriving commercial and residential development on the Tucson’s near west side, as well as the historic and cultural projects expanding in this area known as “Tucson’s birthplace.”
From time to time, Water – Use It Wisely features guest bloggers who write about topics related to water and water conservation. The author of this blog, James McAdams, is the superintendent of public information and conservation with Tucson Water. Tucson Water is a department of the City of Tucson, Arizona, government and operates as a public water utility serving 725,000 residential, commercial and industrial customers both within and outside of the city’s boundaries.